Cylinder for internal-combustion engines



A. H. R. FEDDEN AND L. F. G.,BUTLER.

CYLINDER FOR INTERNAL COMBUSTION ENGINES.

APPLlcMIoN FILED JULY 3,1919.

1,346,535. Patented July 13, 1920.

2 SHEETS-SHEET l.

A. HI R. FEDDEN AND L. F. G. BUTLER.

CYLINDER FOR INTERNAL COMBUSTION ENGINES.

APPLICATION FILED JULY 3,1919.

'Patented July L3, 1920.

2 SHEETS--SIIELI` 2.

@www JI" wx UNITED STATES PATENT OFFICE. i

,ALFRED HUBERT ROY FEDDEN AND LEONARD FREDERICK GEORGE BUTLER, 0F BRISTOL, ENGLAND, ASSIGNORS OF ONE-THIRD T0 THE COSMOS ENGINEERING COMPANY LIMITED, OF BRISTOL, ENGLAND.

CYLINDER FOR INTERNAL-COMBUSTION ENGINES.

Specification of Letters Patent. Patented July 13 1{)2() Application filed July 3, 1919. Serial No. 308,639.

Z '0 all whom zt may] concern:

Ee it known' that we, ALFRED HUBERT ROY FEDDEN and LEONARD FREDERICK GEORGE BUTLER, subjects of the King of England, residing at F ishponds, Bristol, Gloucester, England, and St. Andrews Park, Bristol, Gloucester, England, respectively, have invented certain new and useful Improvements in Cylinders for Internal-Combustion Engines, of which the following is a specification.

This invention is for improvements in or relating to the cylinders of air-cooled internal-combustion engines and has for its object to provide an improved construction of cylinder of the type described in the specification accompanying patent application Serial No. 263,590, filed November 21, 1918.

According to the said prior specification, a cylinder is formed with the highest portion of its head integral with it and devoid of upstanding projections, and there is combined with it a cap which is stitfened against buckling by hoods and pillars all tied together by parallel radiation fins. This cap is vflat on its underside and is secured on the iat upper surface of the head by studs dispoed both centrally and around the pe;l riphery.

In the particular embodiment of the invention described Iin the said prior specification, the cylinder was made of steel and integral cooling fins were formed on it over the greater parts of its length. The cap was made of aluminium and arranged, as shown in the drawings, to provide for three valves in the cylinder-hea According to the present invention, a cylinder for an internal-combustion engine comprises a cylindrical steel barrel having smooth outer walls and a fiat end, an aluminium or other cap similar to that abovementioned secured on the flat end, and a sleeve formed with radiating fins surrounding and secured on the outer curved face of the barrel.

Preferably the sleeve is made of aluminium or other material having a high thermal conductivity, and it is preferably secured in place by shrinking it on to the steel barrel after both sleeve and barrel have been ground perfectly smooth. By this.

means, good contact 'and therefore good thermal conductivity from the steel to the aluminium is insured. y

In the preferred construction, the cooling fins are machined on the aluminium sleeve after it has been shrunk on to the steel barrel.

In the accompanying drawings Figure 1 is a longitudinal section on the line l-l-l of Fig. 2, and

Fig. 2 is a plan of the complete cylinder.

Like reference characters indicate like parts in both figures.

Referring to these drawings, the steel cylinder A is formed with a dat head A1 having two inlet ports and two exhaust ports formed in it. The outer surface of the cyl.- inder' is ground smooth, being flat on top and cylindrical over the rest of the surface except for a flange or lugs A2 whereby the cylinder is secured to the crank-case of the engine.

An aluminium cap, similar to that described in the above-mentioned earlier specification, is secured on the flat cylinder-head A1 by pairs of studs B vdisposed near the center and studs B1 disposed around the periphery in pairs symmetrically about diametral lines 90 apart in the plan of the cap. The cap is formed Without projections on .its under face and is ground fiat, and this arrangement of studs insures that it is held in intimate contact with the cylinder-head,`whereby good thermal conductivity is obtained, and the heat generated in the cylinder is rapidly conveyed to the cap where it is dissipated.

The cap is formed as a flat plate C which is reinforced and stiil'ened against buckling by the hoods C1 C2, which also constitute the inlet and outlet passages communieating with the inlet and outlet ports A3 Ai4 respectively. The plate C is located on the head A1 by dowel-mcmbers comprising rings of copper or other metal of high thermal conductivity let into recesses in both the head A1 and the plate C around the inlet ports. The various hoods are connectedA together by cooling fins cast integral with them as shown at C3 in Fig. 1, and the hoods C2 for the exhaust gases are also provided with special cooling fins C4 (Fig. 2) to insure that they shallA not become overheated.

Further means of stiffening the cap and i, dissipating theheat consists of the illars C5 which also receive the studs B. special circumferential cooling iin C6 is formed around the periphery of the plate C as close to its lower face as convenient. Two openings C7 are provided in the cap C to accommodate the sparking plugs for the cylinder.

The cooling of the body of the cylinder A is effected by 'an aluminum sleeve having aseries of fins or ribs D1 formed on it. The sleeve is ground smooth internally and shrunk on to the cylinder and it may, if desired, be pegged in position.` A good it of the sleeve on the barrel is essential in order that a high thermal conductivity may be insured. It is preferred to form the fins l)1 by machining them after the sleeve has been secured on the cylinder A. A small rib A5 may be provided on the outside of the cylinder A to locate the sleeve D, which is located at the other end of the cap C. In order to allow for the unequal expansions of the steel and aluminum, the length of the sleeve D is made slightlyless than the length between the rib A5 and the end of the cylinder. v It will be seen that in the above described cylinder all the explosion forces are taken by the steel barrel and head, which is much stronger than aluminum, but that the advantages of aluminum for heat dissipation are fully retained. 'Further the attachment Uof the cylinder of the crank-case offers no special diiliculties since the feet A2 are intcgral with the steel barrel which takes the stresses. l

l What we claim as our invention and desire to secure by Letters fatent is 1. For an internal-combustion engine, a cylinder comprising in combination a barrel provided with radiating fins and having an integral flat head devoid of upstanding projections, and -a'cap having four hoods serving as inlet and outlet ports, lat as to its underside-secured'on the saidilat head by pairs of studs disposed centrally (as at B) and symmetrically about diametral lines 90 apart (as at B1), as illustrated in Fig. 2 of the accompanying drawings.

2. For an internal combustion engine, a cylinder comprising in combination, a cylindrical steel barrel having a smooth outer Wall and a fiat end, an aluminum cap stiffened against buckling by hoods and pillars all tied together by parallel radiation fins ,secured on the said fiat end, and a sleeve formed with radiating ns surrounding and secured in intimate contact with the outer curved surface of the barrel.

3. For an internal combustion engine, a cylinder comprising in combination, 'a cylindrical steel barrel having a smooth outer wall and a iiat end, an aluminum cap stiffened against buckling by hoods and pillars all tied together by parallel radiation fins secured on the said flat end by pairs of studs disposed centrally and symmetrically about diametral lines 90o apart, and a sleeve formed with radiating fins surrounding and secured in intimate contact with the outer curved surface of the barrel.

4. For an internal combustion engine, a cylinder comprising in combination, a cylindrical steel barrel having a lsmooth outer Wall and a flat end, an aluminum cap stiffened againstibuckling by hoods and pillars all tied together by parallel radiation ins secured on the said fiat end, and a sleeve formed of aluminum and shrunk onto said barrel, and provided with radiating fins machined on it after'it is secured on the barrel.

y In testimony whereof we have signed our names to this specification in the presence of two subscribing witnesses.

ALER'ED HUBERT ROY EEDDEN. LEONARD FREDERICK GEORGE BUTLER.

Witnesses:

G. W. GoLDEN, R. TREGASKI. 

